8<--- cut here --- Unable to handle kernel paging request at virtual address fee00001 [fee00001] *pgd=80000080007003, *pmd=00000000 Internal error: Oops: a06 [#1] PREEMPT SMP ARM Modules linked in: CPU: 1 PID: 19521 Comm: syz-executor.0 Not tainted 5.17.0-rc7-syzkaller #0 Hardware name: ARM-Versatile Express PC is at __raw_writeb arch/arm/include/asm/io.h:88 [inline] PC is at io_serial_out+0x38/0x40 drivers/tty/serial/8250/8250_port.c:458 LR is at io_serial_out+0x24/0x40 drivers/tty/serial/8250/8250_port.c:458 pc : [<808e1f10>] lr : [<808e1efc>] psr: 60000093 sp : 8571bd48 ip : 8571bd48 fp : 8571bd64 r10: 00000001 r9 : 00000fff r8 : 85254400 r7 : a0000013 r6 : 824f1390 r5 : 00000002 r4 : fee00001 r3 : 00000000 r2 : 00000002 r1 : 00000000 r0 : 824f1390 Flags: nZCv IRQs off FIQs on Mode SVC_32 ISA ARM Segment none Control: 30c5387d Table: 85622bc0 DAC: 00000000 Register r0 information: non-slab/vmalloc memory Register r1 information: NULL pointer Register r2 information: non-paged memory Register r3 information: NULL pointer Register r4 information: 0-page vmalloc region starting at 0xfee00000 allocated at pci_reserve_io+0x0/0x38 arch/arm/mm/mmu.c:1028 Register r5 information: non-paged memory Register r6 information: non-slab/vmalloc memory Register r7 information: non-slab/vmalloc memory Register r8 information: slab kmalloc-512 start 85254400 pointer offset 0 size 512 Register r9 information: non-paged memory Register r10 information: non-paged memory Register r11 information: non-slab/vmalloc memory Register r12 information: non-slab/vmalloc memory Process syz-executor.0 (pid: 19521, stack limit = 0x8571a000) Stack: (0x8571bd48 to 0x8571c000) bd40: 824f1390 00000000 824f1390 a0000013 8571bd94 8571bd68 bd60: 808e3d48 808e1ee4 808b6740 808def80 ebc83000 824f1390 00000001 85254400 bd80: 824f1390 a0000013 8571bda4 8571bd98 808daedc 808e3c18 8571bdc4 8571bda8 bda0: 808dd294 808dae98 ebc83000 ebc8526c 00000040 ebc83000 8571bdd4 8571bdc8 bdc0: 808dd304 808dd230 8571be54 8571bdd8 808bdb1c 808dd300 80275e78 83fe6780 bde0: ffffffff 00000000 ffffffff 85254474 00000001 00000fff 819082b0 55555556 be00: 00000000 00000000 ebc85000 8571be7c 00000001 8571be7c 00000000 ebc83000 be20: 00000001 8571be7c 806785f4 00000000 85622300 85254400 808bea20 00000009 be40: 20000080 85254400 8571be6c 8571be58 808bea3c 808bd740 00000000 816df30c be60: 8571bf14 8571be70 808b9aa8 808bea2c 00000000 d128f410 40003231 00000000 be80: 00000012 00000001 83a6ad90 854aed80 00000005 00000036 8571bef4 8571bea8 bea0: 80688218 8067e058 00000001 00000054 00000012 8571bec4 84602010 82cb0550 bec0: 20005412 854aed0b 8571beb8 854aed80 00000005 d128f410 81f290f0 20000080 bee0: 854aed80 d128f410 8571bf14 00005412 00000000 854aed81 20000080 854aed80 bf00: 00000005 83a6ad90 8571bfa4 8571bf18 804a4c70 808b9290 820a55ec 8209f3b0 bf20: 0012bfc8 83fe6780 83fe6ea0 820a55f0 00000036 60000010 820a55e8 83fe6780 bf40: 820a55f0 00000036 8571bf64 8571bf58 816db0f8 816dafc4 8571bf84 8571bf68 bf60: 816dae80 816db0e8 60000013 00000000 0012bfc8 d128f410 8571bf9c 00000000 bf80: 00000000 0012bfc8 00000036 802002a4 83fe6780 00000036 00000000 8571bfa8 bfa0: 80200060 804a4b6c 00000000 00000000 00000005 00005412 20000080 00000000 bfc0: 00000000 00000000 0012bfc8 00000036 7eae0312 76f346d0 7eae04a4 76f3420c bfe0: 76f34020 76f34010 000163a0 0004bf80 60000010 00000005 00000000 00000000 Backtrace: [<808e1ed8>] (io_serial_out) from [<808e3d48>] (serial_out drivers/tty/serial/8250/8250.h:120 [inline]) [<808e1ed8>] (io_serial_out) from [<808e3d48>] (serial8250_set_THRI drivers/tty/serial/8250/8250.h:140 [inline]) [<808e1ed8>] (io_serial_out) from [<808e3d48>] (__start_tx drivers/tty/serial/8250/8250_port.c:1568 [inline]) [<808e1ed8>] (io_serial_out) from [<808e3d48>] (serial8250_start_tx+0x13c/0x234 drivers/tty/serial/8250/8250_port.c:1667) r7:a0000013 r6:824f1390 r5:00000000 r4:824f1390 [<808e3c0c>] (serial8250_start_tx) from [<808daedc>] (__uart_start+0x50/0x54 drivers/tty/serial/serial_core.c:127) r7:a0000013 r6:824f1390 r5:85254400 r4:00000001 [<808dae8c>] (__uart_start) from [<808dd294>] (uart_start+0x70/0xd0 drivers/tty/serial/serial_core.c:137) [<808dd224>] (uart_start) from [<808dd304>] (uart_flush_chars+0x10/0x14 drivers/tty/serial/serial_core.c:548) r7:ebc83000 r6:00000040 r5:ebc8526c r4:ebc83000 [<808dd2f4>] (uart_flush_chars) from [<808bdb1c>] (__receive_buf drivers/tty/n_tty.c:1553 [inline]) [<808dd2f4>] (uart_flush_chars) from [<808bdb1c>] (n_tty_receive_buf_common+0x3e8/0x12c8 drivers/tty/n_tty.c:1645) [<808bd734>] (n_tty_receive_buf_common) from [<808bea3c>] (n_tty_receive_buf+0x1c/0x24 drivers/tty/n_tty.c:1674) r10:85254400 r9:20000080 r8:00000009 r7:808bea20 r6:85254400 r5:85622300 r4:00000000 [<808bea20>] (n_tty_receive_buf) from [<808b9aa8>] (tiocsti drivers/tty/tty_io.c:2293 [inline]) [<808bea20>] (n_tty_receive_buf) from [<808b9aa8>] (tty_ioctl+0x824/0xa90 drivers/tty/tty_io.c:2692) [<808b9284>] (tty_ioctl) from [<804a4c70>] (vfs_ioctl fs/ioctl.c:51 [inline]) [<808b9284>] (tty_ioctl) from [<804a4c70>] (do_vfs_ioctl fs/ioctl.c:834 [inline]) [<808b9284>] (tty_ioctl) from [<804a4c70>] (__do_sys_ioctl fs/ioctl.c:872 [inline]) [<808b9284>] (tty_ioctl) from [<804a4c70>] (sys_ioctl+0x110/0xaa0 fs/ioctl.c:860) r10:83a6ad90 r9:00000005 r8:854aed80 r7:20000080 r6:854aed81 r5:00000000 r4:00005412 [<804a4b60>] (sys_ioctl) from [<80200060>] (ret_fast_syscall+0x0/0x1c arch/arm/mm/proc-v7.S:64) Exception stack(0x8571bfa8 to 0x8571bff0) bfa0: 00000000 00000000 00000005 00005412 20000080 00000000 bfc0: 00000000 00000000 0012bfc8 00000036 7eae0312 76f346d0 7eae04a4 76f3420c bfe0: 76f34020 76f34010 000163a0 0004bf80 r10:00000036 r9:83fe6780 r8:802002a4 r7:00000036 r6:0012bfc8 r5:00000000 r4:00000000 Code: e6ef5075 e0844001 e7f34054 e2444612 (e5c45000) ---[ end trace 0000000000000000 ]--- ---------------- Code disassembly (best guess): 0: e6ef5075 uxtb r5, r5 4: e0844001 add r4, r4, r1 8: e7f34054 ubfx r4, r4, #0, #20 c: e2444612 sub r4, r4, #18874368 ; 0x1200000 * 10: e5c45000 strb r5, [r4] <-- trapping instruction